Laboratoire de Chimie de Coordination
UPR 8241

Molécules et Composites pour l’Optique

Isabelle Malfant, Responsable d’équipe, Pr, UPS
isabelle.malfant@lcc-toulouse.fr
+33 5 61 33 31 01

Permanents :

Bénédicte Garreau-de Bonneval, Mdc, UPS
benedicte.debonneval@lcc-toulouse.fr
+33 5 61 33 31 52

Pascal Lacroix , DR
CV Pascal LACROIX au format PDF
pascal.lacroix@lcc-toulouse.fr
+33 5 61 33 31 88

Kathleen Moineau , DR
CV Kathleen MOINEAU au format PDF
kathleen.chane@lcc-toulouse.fr
+33 5 61 33 31 88

Marine Tasse , Technicienne chimiste
marine.tasse@lcc-toulouse.fr
+33 5 61 33 31 88

Non Permanents :

 Joëlle Akl, doctorante MESR
+33 5 61 33 31 12

 Daniel Hernandez, doctorant, bourse Mexique
CV Daniel HERNÁNDEZ MALDONADO au format PDF
+33 5 61 33 31 12

 Christina Jimenez-Curiel doctorante UNAM (Universitad Nacionale Autonomia de Mexico) 31 oct 2012 - 31 mai 2013

 Chelmia Billot, stagiaire M2R chimie, Toulouse

Anciens non permanents :
Liste détaillée au format PDF

The design and characterization of new molecular photoactive materials are at the heart of our group. The materials currently under consideration have mainly interesting properties for optical storage (photochromic), photovoltaics (electron donors and acceptors) and the nonlinear optical switching. Our studies are located on the border of two key themes : photonics and organic electronics. New developments are also dealing with photodynamic therapy.

Keywords : Organic Photovoltaïcs - Ni bis-dithiolene complexes - Donor small molecules - Non linear Optics - Molecular Switching - Photochromism - Ruthenium complexes - Nitrosyl ligand - Optical data storage - Photodynamic Therapy - Two Photon Absorption

Organic Materials for Photovoltaics

Organic photovoltaics (OPVs) promise a remarkable cost reduction of photovoltaic (PV) energy, if large improvements of efficiency and lifetime could be achieved. OPV cells are based on Donor/Acceptor molecules. Our previous investigations concerned materials leading to columnar liquid crystal (CLC) structures :

Optical microscopy for CLC complex, in transmission with slightly uncrossed polarizers, observed at room temperature

These molecules absorb strongly up until near-infrared (NIR). We have been working on nickel bis-dithiolene (Ni-bdt) complexes as new OPV acceptors and we succeeded, by using appropriate ligands, in structuring some of them in hexagonal columnar phases.

X-Ray diffraction pattern (left) of a single domain of (Ni-bdt) which exhibits Bragg peaks characteristic of hexagonal columnar mesophase (right)

We now turn our activities through the design and synthesis of innovative acceptors and low band gap new donor small molecules. We combine experiment (synthesis of materials) and theory (theoretical calculation) in order to optimize the materials. Thanks to new collaborations established with LAAS and LAPLACE Laboratories, we perform thin films engineering and optical/electrical characterizations to set up new photovoltaic cells.

Ruthenium Nitrosyl Systems

The ruthenium nitrosyl complexes offer a large variety of physical-chemical properties. In particular, they are of great interest in optical data storage as well as for therapeutic applications.

Photoinduced Linkage Isomerisation

These complexes are characterized by the existence of long-lived metastable states (t > 10⁷s) for specific irradiation at a temperature close to ambient temperature. The different states have different Ru-NO conformations which are responsible for a high change in the refractive index, a very important parameter for holographic data storage. [RuCl(py)₄(NO)](PF₆)₂.1/2H₂O (py=pyridine) complex studied previously in the group is high of interest because of its complete molecular photoswitching at the solid state.

Our results show that such photochromic composites could be obtained when the complexes are embedded in polymer or silica matrices.

Xerogel of [RuCl(py)₄(NO)](PF₆)₂.1/2H₂O, french patent n° 0900126/ extension PCT

NO PhotoRelease

The ruthenium nitrosyl complexes have also the property to release NO upon irradiation which is very important for therapeutic applications. Indeed, the NO molecule (Nobel Price of medecine in 1998) is involved in several physiological processes (blood pressure regulation, neurotransmission, cancer cells treatment,….). Nevertheless, NO has also the ability to induce apoptosis (cell death) in healthy cells. Development of site-specific NO donors is therefore beneficial in selective killing malignant cells. Phototriggered NO release provides one such strategy. Our strategy is based on the use of appropriate two photon absorption (TPA) antenna.

Ru-NO + H₂O → Ru-H₂O + NO

P, K. Mascharack ACS Med. Chem. Lett., 2010, 1(4), 180-183

NLO Materials

Multi-functional materials and molecular switches have long been a traditional interest of our research. Along this line, the possibility to switch the NLO response of a molecule in an hybrid material by mean of any additional function (e.g. magnetic, conducting or photochromic properties) is investigated. Our expertise is based on computational chemistry, which has become an important tool for providing the efficient guidelines required by synthetic chemistry and physics, to target the microscopic origin of the NLO effects. Among various possibilities, switches can be obtained by :

- Optical effect through the total NLO extinction obtained after Ru-NO → Ru-ON isomerization in specific molecules selected by computational methods.

- Magnetic effect through a spin crossover phenomenon, in Iron(II) metal complexes, like in the [Fe(Tren)]²⁺ system shown below, where the magnetic (c_M) vs. NLO response (I_HRS) correlation is clearly established.

The [Fe(Tren)]²⁺ cation subjected to a spin crossover phenomenon between 200 and 300 K

These investigations are based on a fruitful network of collaborations (Bordeaux, Valence, Kiev, Mexico).

Publications

2012 

“Magnetism and Molecular Nonlinear Optical Second-Order Response Meet in a Spin Crossover Complex”
S. Bonhommeau, P.G. Lacroix, D. Talaga, A. Bousseksou, M. Seredyuk, I.O. Fritsky, V. Rodriguez
J. Phys. Chem. C 2012, 116, 11251-11255.

 “Structural Influence on the Photochromic Response of a Series of Ruthenium Mononitrosyl Complexes”
B. Cormary, S. Ladeira, K. Jacob, P.G. Lacroix, T. Woike, D. Schaniel, I. Malfant
Inorg. Chem. 2012, 51(14), 7492-7501.

"Towards Bi-functional Materials with conducting, photochromic and spin crossover properties"
L. Valade, I. Malfant, C. Faulmann
L. Ouahab,. (ed.) Handbook of Multifunctional Molecular Materials, Pan Stanford Publishing, Singapore (in press).

“Synthesis, X-ray crystal structures, optical properties and modelling data of neutral bis(1,2-dithiolene) nickel complexes of the “non-cyclic SR” family”
Thanh-Tuan Bui , Minh Ha Vuong, Bénédicte Garreau-de Bonneval , Fabienne Alary, Jacob Kane, Carine Duhayon , Alix Sournia-Saquet and Kathleen I. Moineau-Chane-Ching
New J. Chem., 2012, 36, 2033-2041

 

2011

Discotic nickel bisdithiolene complexes : synthesis, optoelectrochemical and mesomorphic properties
Bui T.-T., Thiebaut O., Grelet E., Achard M.-F., Garreau-de Bonneval B., Moineau-Chane Ching K. I.
Eur. J. of Inorg. Chem, 2011, 17, 2635-2676

Columnar Benzoperylene-Hexa- and Tetracarboxylic Imides and Esters : Synthesis, Mesophase Stabilisation and Observation of Charge-Transfer Interactions between Electron-Donating and Electron-Accepting Imides
Kelber J., Achard M.-F., Garreau-de Bonneval B., Bock H.
Chem. Eur. J., 2011, 17 (29), 8145-8155

Synthesis, Crystal Structures, and Solid State Quadratic Nonlinear Optical Properties of a Series of Stilbazolium Cations Combined with Gold Cyanide Counter-Ion
Lacroix P. G., Munoz M. C., Belén Gaspar A., Real J. A., Bonhommeau S., Rodriguez V., Nakatani K.
J. Mater. Chem. 2011, 21, 15940-15949

The three-dimensional intermolecular network formed via water molecules in trans-bis(nitrito-kN)tetrakis(pyridine-kN)ruthenium(II) dehydrate
Buron-Le Cointe M., Cormary B., Toupet L., Malfant I.
Acta Cryst., 2011, C67, m375-m377.